Pipe system for kilns



df/afny' 3 Sheets-$heet 1 F. M'. CREIGHTON ET AL PIPE SYSTEM FOR KiLNS 9d Nov. 20. 1920 Dec. 4 1923.

Dec. 4 1923. l,7,595

F. M. CREIGHTON ET AL PIPE SYSTEMFQR KILNS Filed Nov. 20. 1920 a Sheets-Sheet s Patented Dec. 4, 1923.

- pr ST FRANK M. CREIGHTON, OF AMEBICUS, GEORGIA, AND CHARLES J. WILLIAMS, JB., 0]?

JACKSONVILLE, FLORIDA, ASSIGNORS TO MOORE DRY KILN COMPANY, OF JACKSON- VILLE, FLORIDA, A CORPORATION OF FLORIDA.

PIPE SYSTEM FOR KILNS.

Application filed November 20, 1920. Serial No. 425,589.

To all whom it may concern:

Be it known that we, FRANK M. CnmoH- TON and CHARLES J. VILLIAMS, Jr., citizens of the United States, residing, respectively, at Americus, in the county of Sumter and State of Georgia, and Jacksonville, in the county of Duval and State of Florida, have invented certain new and useful Improvements in Pipe Systems for Kilns, of which the following is a specification.

Our invention relates to an improvement in dry kilns and method of curing lumber, and more particularly to a pipe system for kilns.

The present invention is designed for curing both hard woods and soft woods, such as oak, gum, and whitelpine, redwood and cedar, and it consists in a pipe system in which the major portion of the piping is located at the unloading or dry end of the kiln instead of at the green end of the kiln, and in this respect it is an improvement on Letters Patent No. 769,102, granted to La- F'a ette Moore, Aug. 30th, 1904.

n the accompanying drawings:

Fig. 1 is a longitudinal sectional view through our improved kiln;

Fig. 2 is a horizontal section showing the H-shaped steam spray pipe in the top of the green or feed end of the kiln;

Fig. 3 is an end view.

The numeral 1 represents a kiln of suitable construction and dimensions, and the end 2 at the left is the inlet or green end of the kiln, it having the usual arrangement of track rails 3, extending therethrough fromthe green or loading end and then to the dry or unloading end 4.

In the construction shown in Fig. 1, the piping 5 extends from a header 6, located some distance from the loading or green end 2, to the dry or unloading end, and from that point the piping extends back approximately half the length of the kiln to a point 7, and then back again to the header 8. at the bottom of the dry or unloading end 4 of the kiln. The sections -of pipe are connected by brass joint unions 10.

At the green or loading end in this improved kiln there is no piping whatever, and no ventilation. In the pipe system set forth in patent granted LaFayette Moore of Aug. 30t 1904, the piping was located at the green or loading end of the kiln where the lumber entered the kiln. In the present system it is just the reverse, or, in other words, there are no heating coils whatever at the green or loading end.

There is no ventilation at the green end of the kiln. \Ve wish to make the green end ofthe kiln a kind of sweat box or dead air space, for softening the fibre of lumber and opening the pores. In drying partially airdried lumber, the very humid atmosphere in this space will break the shell or crust of the partially air-dried stock and prepare it for the higher temperature which follows.

This method isemployed for drying partially air-dried lumber such as oak flooring, and also for green lumber such as white pine lumber, cedar shingles and redwood, green from the saw.

Thus it is the intention to subject the stock when it enters the kiln to a moist air and low temperature and let it move progressively towards the hot and dry end of the kiln, the arrangement of pipes as described giving this result.

Thus there are three coils only, so arranged that there is no heat whatever at the green or loading end where the lumber is adapted to be sweated, and from there the piping is such that the minimum amount of heat is in the direction of the loading end and gradually increased by the increased number of coils at or toward the dry or unloading end of the kiln.

An H-shaped steam spray pipe 11. is located at the green end, as illustrated in Fig. 1, to provide the moisture.

Ventilators 12 are located at intervals in the roof, as shown in Fig. 1.

Thus it will be seen that upon entering the kiln the stock is subjected to a moist air and a low temperature. and the lumber being on trucks mounted on rail 3 is, moved gradually toward the hot and dry end of the kiln. This method is new and differs from the common practice in which the material to be treatedis subjected to heat immediately on entering the kiln.

Most of the pipe is installed at the unloading end, the lumber being hot, together with the increased amount of pipe at the dry end creates a longitudinal movement of air and in this way we get an internal circulation. The tendency of the heat waves drying certain kinds of.

in the inside of the kiln is to move to the coldest end and in this way we find that the heat waves move from the unloading end up next to the roof back down to the green end of the kiln and down under the heating coils. As will be observed from the drawing, there are no heating coils under the tracks at the green end of the kiln, and when the heat waves move from the dry end overhead toward the green end it forms a circle by moving down below the tracks and back under the blank space to heating coils again. In short. we get a circle or longitudinal movement. It will he observed from the drawing that there are no ventilators 12 above the dead air space between the track and the top header. 5

By reference to the arrows in Figure 1, the movement of the air through the lumher will be understood.

This circulatory movement of the air through the kiln and lumber is what dries the lumber and it constitutes a very essential feature of the present invention. The spray at the loading end forces the air downward and facilitates this circular movement of the air in the kiln, after which the air travels more or less horizontally in the space at the bottom of the kiln and is drawn toward the unloading end and upwardly as a result of its becomingheated by our improved piping system, and as it becomes heated it passes upwardly and again forwardly through the top of the kiln. In this way the air circulates through and through the lumber carried on the trucks. We claim: 1. A dry kiln comprising a housing housing is open throughout its length for the passage of said material, the entrance zone of said housing beingunprovided with heating means but provided with steam moisteningmeans, for moistening the material heating means ,for the remainder of said housing means so arranged as to disseminate a minimum of heat adjacent said entrance zone and a maximum of heat adjacent the discharge end of said housing, the whole so arranged that material is steamed but not dried upon its entrance into said housing and is subjected to increasing degrees of heat as it progresses towards the discharge end thereof.

2. The combination in a dry kiln, of a pipe system extending throughout the lower portion thereof for heating the kiln, and a steam spray located at the ceiling and discharging downwardly into the kiln. 3. [he combination in a dry kiln, of a pipe system extending throughout the lower portion thereof for heating the kiln, and a steam spray located at or near the ceiling of the green end of the kiln and discharging downwardly into the kiln.

4. The combination in a dry kiln, of a pipe system extending throughout the lower portion thereof for heating the kiln, and an H-shaped steam spray pipe located in the green end of the kiln and discharging moisture downwardly thereinto.

In testimony whereof we aflix our signatures.

FRANK M. CREIGHTON. CHARLES J. WILLIAMS. JR 

